IMHO, Innovation has been lacking in the SUV market.
My Toyota FJCruiser represents some degree of engineering and design innovation. It's 20mpg can be easily cut in half by using cheap gas and pretending it's a sportbike

Otherwise it does well with it's torque-monster-V6 engine on gas mileage.
Fuel prices are high, but not high enough to force most FJ owners to give up these cool vehicles. Even today, if an FJ winds up at a used car lot, it doesn't take long to sell.
This isn't the case with other SUVs. I was caught in some intense rain recently and some of the cars I "dodged" were newer Chevy, Ford, and Mercury SUVs that couldn't handle being that much water.
If someone is envious with how easy it is to clean the inside of an FJ (they don't have carpet), one can pick up smaller Toyota or Honda alternatives also that have rubber floors and floormats. In these times, it's also cool to strap fancy HD-DVD or Satellite players inside these vehicles now - kids have more fun, than with inferior factory built-in alternatives that cost much more.
One can look good in an Escalade, but folks like me will still have more fun. That is what is missing from the American Auto Industry today. When the economy is bad, customers want innovation - which translates to better fuel economy and the flexibility to still achieve the things they need, whether it be cool gadgets, transporting large families, or continuing to enjoy a particular outdoor sport.
Until then, buyers will turn to the used car supply for inexpensive SUVs and Trucks to support whatever their needs are.